Strange whining sound coming from engine compartment on target boost

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For a while, strange whining sound has been coming from engine compartment on target boost. Only today did I manage to record sort of a decent video clip where sound could be somewhat easily heard. So far I have no idea what a hell this could be short of intake leak somewhere. I've posted a question on nasioc, let's see what that brings. Below is nasioc quote:

Hey guys, hopefully someone will be able to help me a bit with identifying a strange whine noise coming on load/target boost. This has been happening since I went to stage 2. It's very hard to tell for sure where exactly it is coming from, to me being in driver
position it seems like it's coming from driver side, even if all windows rolled down.

Power mods:

  1. Turboback exhust (SPT catback + catted divorced Perrin downpipe).
  2. Stage 2 Octane 93 COBB Access Port tune.

I've posted some clips here before but the quality wasn't that great, today somehow I managed to record better clip with all windows rolled up:

Strange whine noise on target boost from Vlad Kulchitski on Vimeo.

At first it may sound normal, so to qualify this I've outlined at which point in video this sound can be observed, it's not terribly annoying, but distinctive whining sound, so at the following times:

  1. 00m03s — 00m05s
  2. 00m10s — 00m12s
  3. 00m22s — 00m24s
  4. 00m59s — 01m01s
  5. 00m02s — 01m04s

Any help and hints will be appreciated,
Thanks,
Vlad
p.s. maybe I am overly paranoid, I would be happy if this was the case

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